Electrically-driven sewing machine



Juiy 7, 1931; c. w: HDOUBLER ELECTRICALLY DRIVEN SEWING MACHINE Filed Oct. 8, 1924 2 Sheets-Sheet 1 Inventor 2 Shuts-Sheet 2 C. W. H'DOUBLER ELECTRICALL?! DRIVEN SEWING MACHINE Filed 001- 8, 1924,

Jilly 7, 1931.

Inventor I WWW S AT-Es July 7 1 931 PATENT? OFFlCE A,

CHARLES w. irDoUBLm-or RAGINE, wrscousn'q 1 ELECTRiCALLY-DRIVEN SEWING MACHINE Application med, octopus, 1924. semi in. 742,483,

' :10 tached and, also, the motor becomes fouled from the'dust and lint incidental to a sewing machine. Furthermore, the said constructions are'not as desirable as a unitary structure.

It is, therefore, one of the objects of my invention to overcome the afore-mentioned objectionable features and provide an electrically driven sewing machine in which the motor is positioned on the under side of the 90 bed-plate of the machine, entirely concealed from view, and forms an integral part thereof.

It is a further object of the invention to provide an electrically driven sewing machine with a motor detachably built on the 'under side ofthe bed-plate of the machine, and so connected with its working mechanism, that the principles therein involved may be applied to any of the standard makes of sewing machines without changing their external appearance and demanding but slight changes in the internal construction.

A further object of the invention is to provide an electrically driven sewingmachine in which the'motor occupies otherwise unoccupied space and is completely encased and protected in a housing provided on the underside of the bed-plate as an integral part thereof, and supplementing the usual cross ribs as reinforcements, thus providing a machine that is strong, durable, simple of construction, not likely to get out of order and is well adapted for the purpose intended.

With the above and other objects in view, which will appear as the description advances, my invention resides in the novel construction, combination and arrangement of arts substantially as hereinafter desc-ri ed, and more particularly defined by the appended claims, it being understood that such changes may be made in the precise embodiment of m lnvention as come within the; scope of said 0 aims.

In the accompanying 'drawin s in which sa-me'parts in all of the views:

the same reference characters indicate the Fig. lisla'sectional view of the rear portion of. myelectrically driven sewing ma,- chine, viewed from the bottom and looking upward, said section being through the centers of the armature and driving shafts;

Fig. 2 is'a view 'of the removable lower half of the rear end of the motor housing showing the lower halves of the supports provided for-the brush members and the rear motor shaft bearing; I

Fig. 3 is a view of the removable lower half of the front'end of the motor housing, showing the lower half of the gear box incorporated therein and the front motor shaft bearing;

Fig. 4 is a side elevation of the improved sewing machine with a part of the goose-neck broken. away to reveal the inner construction, and the bed-plate in vertical section through the center of the driving shaft;

Fig. 5 is a full sized end view of the flattened motor field portion, or stator, demanded in my construction;

Fig. 6 is a full sized view of the clutch and gear wheel carried on the driving shaft; and

Fig. 7 is a cross section of the said clutch taken on the line 46-46 of Fig. 6.

Referring to the drawings the numeral 7 indicates the rear portion of the bed-plate member of my improved electrically driven sewing machine viewed from the bottom and looking upward. This member, besides providing supports for the usual mechanism attached to the bed-plate of a sewing machine, includes as an integral part thereof a complet'e motor housing 11 embodying the portions 8, 8a, 9, 9a, 10 and a cover 38; and, furthermore, supplements the usual cross ribs as reinforcements to said bed-plate.

The portions 8 and 9 are downward extensions of the bed-plates to a plane even with the center of the driving shaft 14 (to be further described later) which is journaled horizontally in two-part bearings provided in the bed-plate. The portion 8, aside from forming a section of the front end of the motor housing, includes a box-1ike cavity, hereinafter termed the gear-box, for supporting sundry gears (to be introduced later in this description). The portions form the side walls of said motor housing and are,

therefore, extended dmvnward the full depth of the housing which is substantially the width of the field member 31 (to be later described) measured from one flat side to the other (Fig. 5).

The portions Sc and 9a (Figs. 3 and 2) are the removable lower halves of sections 8 and 9 respectively and are so proportioned that when in their proper positions their lower edges will be on a horizontal plane with the lower edges of the aforementioned side walls thus providing an even support on the four sides of the said housing for engaging the cover 38 which completes the housing and therewith the bed-plate as a unit.

The aforementioned horizontally extending driving shaft 14 actuates a loop-taker 40 mounted fast on the front end thereof and carries a clutch 44 and gear wheel 29 (to be later described), two cams 41 and 42 for actuating a feed controlling device (not shown) and is provided with a cranked poition 15 on which a connecting rod 16 is journally mounted, and slidingly engaged by a pivoted fulcrum 20, for transmitting motion to an upper two-part, horizontally extending, countershaft journaled in a goose-neck 12 which is secured to the bed-plate by screws 13, said goose-neck being provided with a removable end portion 18 for convenience in assembling.

The forward portion of said two-part shaft actuates a needle-bar and take up mechanism (not shown) in the front end of the gooseneck while the rear portion carries a hand wheel 19; and these two sections are rotated in unison by means of two rollers 22 journally mounted on the protruding ends of a pin 21 rigidly. inserted through the flattened upper end of the connecting rod and are mova )ly engaged in two channels provided in the two crank arms 23 which are splined on the inner ends of the two sections of the said two-part shaft.

It is now clear that in my invention the transmission of motion from a lower drive shaft toan upper countershaft is an exact reversal from the common practice although the means of transmission by a connecting rod sliding through or over a pivoted fulcrum is identical and too well known to the art to need further mention herein; it is pertinent, however, to here state that the two-part upper shaft feature as shown is provided solely to meet the contingent of a possible demand for the conventional, andv long Ja i-used, hand wheel, while it is my desire to provide an electrically driven sewing machine that will be under such perfect control that the rear shaft portion and hand wheel may ultimately be eliminated as undesirable and unnecessary adjuncts thereto.

That the desired electrical operation of the above described mechanism may be. attained an electric motor 24 is positioned within the housing 11 (heretofore described) with the horizontally extending shaft portion 25 in substantially parallel alignment with the driving shaft. 14 and iournaled. in the two housing end portions 8 and l). The forward end portion of said motor shaft supports a pinion mounted fast thereon. which is in mesh with gear wheel 27, and said gear wheel is journaled on a countershaft 6 which is supported in the side walls of the gear box portion of the forward end housing section 8. The gear wheel just mentioned has a tubular pinion 28 secured to and projecting therefrom which is in mesh with a gear wheel 29 mounted on the driving shaft 14 for the purpose of transmitting rotary motion to said shaft at a lesser rate of rotary speed than the rotary speed of the motor through the medium of the gear train. just described.

If the motive mechanism just described is to be adapted to the two-spool or chain-stitch types of sewing machines, neither of which uses bobbins, the gear wheel 29 is to be mounted fast on the shaft 14 and no provision made for disconnecting the motor. If, however, the usual bobbin type is adopted the said gear wheel is to be ournally mounted on said shaft with the inner side butting against a shoulder 54 provided on the shaft. Furthermore said gear wheel is provided with an outwardly pro1ecting portion 53 on the forward side and the outer face of said projecting portion is provided with a series of equally spaced pawllike teeth for engaging a similar series of ratchet-like teeth provided on the inner side of a. clutch 44 which is slidingly mounted on the shaft 14 and prevented from turnin thereon by a key 45 set in said sha t which functions with a key-way through said clutch; and the said clutch is further provided with a groove 49 encircling it near its outer edge.

To provide means for connecting and dis-- connecting the clutch and gear wheel a lever 46 is pivoted on a boss on the under side of the bed-plate portion 7 of the machine by a screw 47 (Fig. 7). The inner portion of said lever is forked and each prong is curved so as to partially encompass the clutch and the end of each prong has an inwardly extended rounded (portion 46a engaged by the aforementlone groove on opposite sides of the clutch with the diametrical center of said rounded portions in direct line with the diametric center of the shaft 14 when the clutch and gearwheelare connected.

Moving the outwardly extending ortion of the lever to the right or left sli es the clutch on the shaft by means of these rounded portions of the lever and either connects or disconnects the clutch and gear wheel as desired. To maintain the desired position of the clutch two notches 52 and 52a are provided on the bottom edge of the sideu'ail oi the bed-plate to engage the lever arm and it is held thus engaged by the wring pressure of the lever arm produced by bending the lever arm upwards sullicientlyto hold the lever arm snugly against the top surface of the notch. The lever arm is shifted from one notch to the other by first pushing it downward the depth of the notch and then from right to left, or the reverse, and to guard against too great a downward movement a formed plate 50 is secured to the bottom of the side rail by screws 51, leaving just sulficient space for the lever arm to freely pass from one notch to the other.

It is now apparent that when the lever arm is in notch 520: the clutch will be held in contact with the gear wheel 29 and motionis transmitted to the drive shaft i l, but if thrown to the rear notch 52 the clutch will. be released and the motor will run free for winding bobbins.

To accomplish this a pulley 48 is splined on the protmd'ing rear end of the motor shaft for transmitting motion by a small spring belt (not shown) to a bobbin winding device (not shown) suppoited. on. the standard portion of the machine.

Assembling the motive elements of my electrically driven sewing machine may be read ily accomplished thus:

1. Place the bed-plate portion on the bench bottom upward;

2. The armature 30,. with the pinion 26 mounted fast thereon, is positioned within the field portion 31 carrying the field coils 32 and together these members are introduced into the housing 11 with one fiat side of the field portion at the bottom, the rounded ends slidingly engaged by the side walls leaving the armature shaft resting in the half bearings provided in the housing end portions 8 and 9;

3. Secure the field portion in place by a. screw 43 through the top side of the housing;

4. Place brush members 33 supports provided in rear housing portion 9 with the carbon brushes engaging the commutator 5 and.

connect said. member with the field coil leads 34 by gripping the metal sleeve portions with thedmetal clips 35 which are scored to said lea s:

Place portion 9a over portion 9 and secure by 36;

6, Journal the previously connected gear wheel 27 and pinion 28 on the counter shaft 6 and position same in gear box portion of section 8 with the ends of counter shaft resting in the half supports provided therein;

screws engaging the threaded holes 7; Place drive shaft 14, with its previously 8. Position the portion 8a (Fig. 3) over portion 8 and secure bv screws engaging the threaded holes 37; and

9. Test and adjust the motor and complete the-operation by fastening the cover 38 to the bottom of the housing by screws 39.

Access to the motor for adjustments or light repairs is readily attained by simply remov ing the cover and, if so desired, the motor parts may be removed by disconnecting the two portions 8a and So.

It is obvious that those skilled in the art may vary the details of construction as well as the arrangement of parts without departing from the spirit of the invention and, therefore, it is not wished to be limited to the. above disclosure except as may be required by the claims. I have, however, preferred to portray this structure as the logical. embodiment of my invention and in this connection it is relevant to disclose that the field member of the motor as shown in Fig. 5 is flattened on. the sides forthe pur Jose of narrowing the motor that the axes oi the motor and.

driving shafts may be on the same horizontal plane and still leave the driving shaft at the proper distance from the sewing plate that the loop-taker mou nted thereon will function with the needle; and it will furtherbe seen that with this arrangement all bearings will be parallel and their horizontal centers on the same plane, thus making it possible to do all machine work demanded on the under side of the bed-plate at one setting which will simplify construction and assure alignment of the various parts W'ha-t I claim as my invention. is:

1. In a sewing'm achine, in combination, a

bed-plate supporting a horizontally disposed hock shaft, a motor having the shaft of the armature portion thereof journaled in the bed-plate adjacent and substantially parallel to the hook shaft, a driving connection be tween the motor and the hook shaft and means for connecting and disconnecting said driving connection.

2. In a sewing machine, in combination, a horizontal bed-plate supporting a horizontally disposed hook-shaft, a motor havin the shaft of the armature portion thereof ournaied in said bed-plate, a driving connection between the motor and the hook-shaft, means for connecting and disconnecting said driving connect on and means for locking the driving connection in either predetermined position.

3. The combination with a sewing machine having a horizontal bed-plate with a motor mounted on the under side thereof, of a drive shaft provided with a shoulder journaled adj acent said bed-plate, a key set in said drive shaft, a clutch member provided with a keyway for engaging said key slidingly mounted on the shaft, a gear wheel engageable with said clutch member journaled on the shaft I abutting said shoulder and having aidriving connection with said motor, means for engaging and disengaging said gear wheel and clutch member, and means for locking the clutch in either predetermined sition.

In testimony whereof I here y attach my signature.

CHARLES W. HDOUBLER. 

